[SL] version 2.8.11 - error: Premature end of script headers

[Prem P. <pre...@gm...>]

After upgrading to SL 2.8.11:
I can access the admin pages and the login page, but after login this error
message appears. (Apache 2.2.8)
 Internal Server Error  The server encountered an internal error or
misconfiguration and was unable to complete your request.
The Apache error.log shows this error line:
Premature end of script headers: login.pl, referer:
http://wz1:79/sql-ledger/login.pl
What could be wrong?

Thanks
Prem